[PATCH 5.10 389/406] bus: mhi: host: Skip MHI reset if device is in RDDM

Greg Kroah-Hartman
2023-09-17T19:43:24Z

From: Qiang Yu <quic_qianyu@quicinc.com>

[ Upstream commit cabce92dd805945a090dc6fc73b001bb35ed083a ]

In RDDM EE, device can not process MHI reset issued by host. In case of MHI
power off, host is issuing MHI reset and polls for it to get cleared until
it times out. Since this timeout can not be avoided in case of RDDM, skip
the MHI reset in this scenarios.

Cc: <stable@vger.kernel.org>
Fixes: a6e2e3522f29 ("bus: mhi: core: Add support for PM state transitions")
Signed-off-by: Qiang Yu <quic_qianyu@quicinc.com>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://lore.kernel.org/r/1684390959-17836-1-git-send-email-quic_qianyu@quicinc.com
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/bus/mhi/host/pm.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/bus/mhi/host/pm.c b/drivers/bus/mhi/host/pm.c
index 7d69b740b9f93..fe8ecd6eaa4d1 100644
--- a/drivers/bus/mhi/host/pm.c
+++ b/drivers/bus/mhi/host/pm.c
@@ -490,6 +490,10 @@ static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl,
u32 in_reset = -1;
unsigned long timeout = msecs_to_jiffies(mhi_cntrl->timeout_ms);

+ /* Skip MHI RESET if in RDDM state */
+ if (mhi_cntrl->rddm_image && mhi_get_exec_env(mhi_cntrl) == MHI_EE_RDDM)
+ goto skip_mhi_reset;
+
dev_dbg(dev, "Triggering MHI Reset in device\n");
mhi_set_mhi_state(mhi_cntrl, MHI_STATE_RESET);

@@ -515,6 +519,7 @@ static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl,
mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0);
}

+skip_mhi_reset:
dev_dbg(dev,
"Waiting for all pending event ring processing to complete\n");
mhi_event = mhi_cntrl->mhi_event;
--
2.40.1